1. Technical Field
The present disclosure relates generally to information processing systems and, more specifically, to power management within a computing system.
2. Background Art
Power management in a computing system involves efficiently directing power to different components of the system. By selectively reducing power to portions of the system that are not currently being used, power needs of the system may be reduced. Power management may be particularly useful for portable devices that rely on battery power, but may also be useful in desktop and server devices. Length of battery life for a portable computing device is often a key metric for user satisfaction with the device. Reducing power to unused portions of the computing system may save battery power by reducing power leakage from the unused portions and thus reducing overall power consumption of the system. For desktop and sever devices, reducing power to unused portions of the computing system to provide reduced power consumption may be useful for a myriad of reasons, including (but not limited to) energy conservation and reduced costs for operational power.
In a computer system with this type of selective power control, individual portions of the system that are not in current use may be thus placed in a reduced power state to save electrical power and, for mobile devices, to extend battery life. Such implementations may wait until a need for a particular portion of the system arises before powering up that portion. Transitioning from a reduced power state to a fully operational state takes a finite period of time. The system may need to wait for the needed portion to be powered up and ready before utilizing that portion, because circuits may not behave predictably if the voltage level is too low.